Furnace wall



May 17, 1932. A. E. SMITH ET Al.

FURNACE WALL Filed Nov. 8, 1930 3 SheetS-Sheet 1 May 17', 1932. A. E. SMITH ETAL FURNACE WALL Filed Nov. 8, 1.930

May 17, 1932. A. E. SMITH ET AL FURNACE WALL Filed Nov. 8, 1930 3 Sheets-Sheet 3 ?atexited ay 1 7 1932 Ammon ii. SMITH, or' NEWTON,

SETTS, ASSIGNOBS TO IBERNITZ FUBNACE APPLIANCE Erica AND BENJAMIN E. SNOW, 0F MELROSE, MASSACHU- COMPANY, OF BOSTON, MASSA- CHUSETTS, CORPORATION or MAssAonUsiiTTs I nummer: WALL Application led November S, 1930. Serial No. 494,812.

This invention relates to furnace walls and is especially concerned with the linings of such walls.

It is now a common practice to line furnace walls with bricks made of highly re fractory material such as silicon ca rbide'. Siicli material greatly increases the life of the wall and is particularl useful in those walls in which tubes are,eni added, the tubes carrying steam or water and either forming part of the circulating system or being use to heat feed water.

The present invention relates more especially to walls of this general type, and it aims to improve the construction of such walls and the bricks used in them with a view to reducing the expense of manufacture, installation and repair, while still producing a wall structure fully as satisfactory as prior constructions.

The nature of the invention will be readily understood from the following description when read in connection with the accompanying drawings, and the novel features will be particularly pointed .out inthe appended claims.

In the drawings,

Figure l is a horizontal sectional view of a water wall embodying features of this invention;

Fig. 2 is a front elevation of a section of the wall shown in Fig. 1;

Fig. 3 is a perspective view on a larger scale showing a portion of a wall and illustrating particularly the construction of the bricks used in the lining;

Figs. 4 and 5 are views similar to Figs. 1 and 2, respectively, showing a slightly modied embodiment of the invention; and

Fig. 6 is a vertical sectional view on the line 6 6, Fig. 4.

Referring first to Figs. 1 and 2, the wall construction there shown com rises a rear section, indicated in general at and a front section or lining B. Located in the front section is a series of tubes 2 which may congin duct steam, water or other fluid medium. These tubes are clamped together and held rigidly in s aced relationship to each other by some suitable clamp construction, that shown in Patent No. 1,7 50,048, granted March 11, 1930, preferably being used. This clamp arrangement comprises a channel bar 3 lying horizontally immediately behind the tubes, a series of U-bolts 4 which embrace the tubes and have their legs extended through the bar 3, and spacing blocks 5 interposed between the tubes and the channel bar. Nuts 6 threaded on the end portions of the U-bolts 4 serve to dra`w them backwardl 'and to clamp the tubes securely against t e blocks and the bar.

The rear wall section A. may be of any suitable construction.v In some installations this rear wall section consists simply of a brick wall with or without insulatin material between it and the tubes. In or er constructions it is made up of blocks or boards of insulating material which are backed upv by a sheet steel casing 7 Fig. l, the casing being secured in place by adapter bolts 8 which are threaded on to the projecting ends of the U-bolts 4, extending throu h the casing and havin nuts 9 threade on them which back up t e casing.

It should be observed that the front and rear wall sections are entirely independent of each other and the rear section may be erected prior to the installation of the front section or lining B. This is a substantial practical advantage both in erecting the wall and also in repairing it.

In the construction shown in Figs. l, 2 and 3 the front section or lining comprises bricks arranged in two opposed series between each adjacent pair of tubes. Considering, 'for example, the two left-hand tubes shown in Figs. 1 and 2, it will be observed that a series of blocks C rest against the extreme left-hand tube while another series of similar blocks or bricks D rest against the next adjacent tube. The bricks in each series are arranged end to end, although the bricks in any individual series do not all rest on each other. As shown in the drawings each brick is grooved on one side for substantially its entire length to fit against one of the tubes 2. The opposite side of each of the bricks C is provided with a laterally extending projection or enlargement 10, and each of the bricks I) is provided on the side thereof opposite to the groove with a similar enlargement 12. It will be seen from an inspection' of the pair of bricks C and D in the upper left-hand corner of Fig. 2, that the projection 12 of the brick D overlies the projection 10 of the brick C and that the contacting faces of these two projections are inclined at an angle of approximately 45. The same relationship exists between the bricks of each opposed pair in vany other part of the facing or lining. The lowermost row of bricks C in Fig. 2 rest on the U-bolts 4 and the bricks D which cooperate with them, respectively, are supported by their engagement with the laterally inclined surfaces of the respective bricks C. This engagement is such, as will be clear from an inspection of Fig.- 2, that the bricks are crowded by gravity, one upon the other, into contact with their respective tubes, thus making a firm engagement which is desirable in order to obtain a proper heat transfer between the bricks and the tubes.

The construction of the individual bricks is better shown in Fig. 3. Each brick may be regarded as having a body portion which, when the bricks are in the wall, lies behind a plane extending through the forward edges of the tubes, and a face portion which lies in front of said tubes or at the fire side of the wall. This face portion is rectangular in outline and is made of substantial thickness. Due to the grooved construction of the bricks, each brick lits' approximately half way around the front face of the tube against which it bears so that two adjacent bricks located at opposite sides of the tube serve to protect substantially the entire width of the front face of the tube from the heat of the furnace.

Itis preferable to have the bricks of each pair `overlap each other at the fire side of the wall and for this reason the projections 10 and 12 of the bricks are extended beyond the adjacent edge of the face portion of the brick. This is clearly shown in Fig. 3 where the projection 10 of the brick C extends beyond the edge face 13 of said brick, the extension having a face 14. A similar face 15 on the extension 12 of the brick D extends oatwardly beyond the edge 16 of the face portion of the brick. Each brick also has an inwardly offset lateral face, that of the brick C being shown at 17 while that of the brick D is shown at 18, and the width of these offsets is substantially equal to the width of each of the faces 14 and 15. The inclined surface 20 of the brick C connects the two offsets of said brick, while a similar inclined face 21 on the projection 12 connects the two oli'sets of the latter brick. These inclined faces rest one upon the other when the bricks are in tlie wall and, due to this offset construction, a part of the face portion of each brick overlaps part of the body portion of the opposing brick. This will be clear from an examination of Fi 3- it being borne in mind that when the rick C has been placed in cooperative relationship to the left-hand tube 2, Fig. 3, the inclined face 2O of this brick will rest on the inclined face 21 of the brick D. At this time the offset portion 14 of the brick C will lie behind that portion of the front face of the brick D which extends above the inclined surface 21. Vhen the bricks are in this position also, that part of the front face of the brick l which extends below the shoulder 20 will lie in front of the face 15 of the brick D. This arrangement substantially closes gaps which otherwise would extend through the lining from front to rear between abutting bricks.

In assembling the bricks they are placed in position between adjacent tubes, one upon the other, a brick of one series following an opposed brick of the other series, and they are held in their cooperative relationship in the wall partly by their interlocking engagement with the tubes and partly by the contact of their inclined faces with each other. It will be observed that these inclined faces extend across the center line of the tubes so that they utilize gravity in causing the bricks to slide one on the other until they are wedged firmly against their respective tubes, the tubes affording lateral support for the bricks. It will be evident, however, that other forms of supports can be substituted for the tubes to perform equivalent functions so far as the support of the bricks isv concerned, withinv in sections, each section being supported on a clamping bar 3, or, more properly, on the U-bolts carried thereby, and key bricks being located at the top of each section so that they can be removed from the fire side of the wall. These key bricks are 4.of such height that when they have been removed, the uppermost blocks C and D in each section can also be removed, after which the lower blocks can easily be taken out.

The construction shown in Figs. 4, 5 and 6 differs from that above in that the body portions of the bricks are so located with reference to the face portions that the o posed bricks between each adjacent pair of tu es are supported in a staggered redescribed chiefly lationship to each other instead ofa 1n rcgistering relationship as shown in Fig. 2. Considering, for example, the bricks E and F it will be seen that the rejection 30 extending laterally from the ody. portion of each brick has inclined faces at its u per and lower ends. The margin of the projection is offset tion of the brick are inset with reference tol said edge, as indicated at 32. Consequently,

each projection of one brick is overlapped by the face portions of two bricks of the opposing series, the same general effect thus being produced as in the construction shown 1n Figs. 1, 2 and 3. v

It should be nbted that in both constructions the inclined surfaces of the blocks or bricks which are in contact with eachother are formed on the body portions of the blocks and lie behind the face portions. The latter portions of the bricks protect the inclined surfaces from ash or slag. The blocks, therefore, can always move one on the other as the wall expands and contracts under changes in temperature.

It is contemplated that the blocks or bricks may be made of any suitablel refractory material. In some cases they aremade of fire clay, or similar compositions, in other cases of cast iron,A and very frequently of silicon carbide or other highly refractory non-metallic material. These members have been referred to herein as blocks or bricks, both terms being used commonly in the trade to designate wall elements of thischaracter.

While we have herein shown and described preferred embodiments of our invention, it

will be understood that the invention may be embodied in other vforms withoutl from the spirit or scope thereof.

Having thus described our invention, what we desire to claim as new is:

` l. In a furnace -wall, the combination departing with a series of upwardl extendin tubes l and a rear wall sectlon bac 'ng up sai tubes, of a front wall section for protecting the surfaces of said tubes at the ire side of the wall, said front section comprising blocks arranged in two opposed series between each pair ofadjacent tubes, the blocks in each series being positioned end to end and eachbearing against a tube, the blocks of one series hav-- ing inclined faces located between the tubes and bearing against similarly inclined faces on the blocks of the other series, and each block having a rectangularA face portion lying in front of the plane of the forward edges of the tubes and each protecting approximately half of the width of the front face of the tube against which it bears.

2. In a furnace wall, the combination with a series of upwardly extending tubes and a rear wall section backing up said tubes, of a front .wall section for protecting the surfaces of said tubes at the fire side of the wall, said front section comprising blocks each having a rectan, `=,rular face portion .of substantial thickness lying infront of the plane' ofthe forward edges of the tubes and each extending approximately half way around the front face of a tube, each block also including a body portion extending rearwardly from said face portion and positioned between the tubes, each pair of adj acenttubes having two tween them with the blocks in each seriesl located end to end, said body portion of each Aopposed series of said blocks positioned bcblock being grooved longitudinally to tit against lits respective tube, and the blocks of.

each serieshaving inclined faces located between the tubes and bearing against similarly inclined faces on the blocks of the other series, said inclined faces serving to cause the blocks to gravitate one on the other into contact with their respective tubes.

3. A furnace wall according to 'preceding4 claim 2 in which a part of the body portion of each block projects beyond the adjacent edge of the face portion thereof, whereby the face portion of .each block of one series 'overlaps the body portion of a block of the opposite series against which it bears and the two overlapping portions are separated from each other by said inclined contacting surfaces of the blocks.

4. A block for. furnace walls of the type in which tubes or similar supports, are included in the wall structure, said block comprising a rectangular front face portion of substantial thickness adapted to be exposed at the fire side of the wall, one side of said block being grooved Vto fit against said support and to extend approximately half way around the front side of the support, and a projection extending from the opposite side adapted to be exposed at the lire side of the wall, one side of said block being grooved to fit against said support and to' extend approximately half way around the front side of the support, the opposite side of said block having a part behind said face portion offset outwardly with reference to the adjacent edge of said face portion and another part offset inwardly with reference to said edge, said offset portions being connected by a laterally inclined bearing face, to bear against a similar face on another block. Y

6. A block for furnace walls of the type in which tubes or similar supports are included in the wall structure, said block comprising a front face portion of substantial thickness' adapted to be exposed at the fire -side of the wall, one side ofsaid block being grooved to fit against one of said supports and to extend approximately half Way around the front side of the support, the opposite side of said block having a part behin'd said face por- 5, tion laterally offset away from the edge surface of said face portion and toward said groove, the latter side of the block also having a projection extending laterally beyond said edge surface4 of said face portion', said projection being provided With a laterally inclined bearing surface, crossing the plane of said edge surface, to fit against a similar surface on another block. v 7 A block for furnace Walls of the type in which tubes or similar supports are included in the Wall structure, said block comprising a quadrangular front face portion of sub# stantial thickness adapted to be exposed at the fire side of the wall and a body portion 1ying behind said face portion, one side of said block being grooved to fit against one of said supports and to extend part Way around the front side of the support, said body portion having a laterally inclined surface to engage a similar surface on another block, and

parts of said body portion being offset from' the edge surface of said face portion.

In testimony whereof we have hereunto signed our names to this specification. ARTHUR E. SMTH.

BENJAMIN H. SNOW. 

